This invention relates to the art of electromagnetically-operated fluid pumps, and more particularly to a new and improved electromagnetic pump which operates at extremely low power.
One area of use of the present invention is implantable drug delivery systems, although the principles of the present invention can be variously applied. The principal requirements for a pump in such applications are low power drain, since the pump must be driven by an implanted battery, and compatibility with the drug being pumped. Other important requirements are that the pump be relatively insensitive to the presence of bubbles in the fluid being handled, be relatively easy to prime, and provide an adequate fluid pressure increase across the pump which is sufficient for the intended uses of the pump. A further requirement is to have low pressure drop across the pump check valve while at the same time providing satisfactory long term sealing against back flow.
It would, therefore, be highly desirable to provide an electromagnetically-operated pump which is safe, reliable, small in size, light in weight, which operates without excessive demand on the available energy supply, which is compatible with drugs or similar liquids to be pumped, which is relatively insensitive to the presence of bubbles in the fluid being pumped and relatively easy to prime, which provides an adequate fluid pressure increase across the pump sufficient for the uses intended, and which allows low pressure drop across the pump check valve while at the same time provides satisfactory long term sealing against back flow.